The present invention relates to a method for obtaining chitin and/or chitosan from insect cuticles. More particularly, the method according to the present invention comprises a first enzymatic hydrolysis of insect cuticles using at least one endopeptidase, separation from the hydrolysis medium of the hydrolyzed cuticles resulting from the first enzymatic hydrolysis, and a second enzymatic hydrolysis of the hydrolyzed cuticles using at least one endopeptidase, excluding exopeptidase.

The present invention is in the technical field of synthetic biology and metabolic engineering. More particularly, the present invention is in the technical field of fermentation of metabolically engineered host cells. The present invention describes a method of making sialylated oligosaccharide by fermentation with a genetically modified cell, as well as to the genetically modified cell used in the method. The genetically modified cell comprises at least one nucleic acid sequence coding for an enzyme involved in sialylated oligosaccharide synthesis and at least one nucleic acid expressing a membrane protein.

The present invention is in the technical field of synthetic biology and metabolic engineering. More particularly, the present invention is in the technical field of fermentation of metabolically engineered microorganisms. The present invention describes engineered microorganisms able to synthesize sialylated compounds via an intracellular biosynthesis route. These microorganisms can dephosphorylate N-acetylglucosamine-6-phosphate to N-acetylglucosamine and convert the N-acetylglucosamine to N-acetylmannosamine. These microorganisms also have the ability to convert N-acetylmannosamine to N-acetyl-neuraminate. Furthermore, the present invention provides a method for the large scale in vivo synthesis of sialylated compounds, by culturing a microorganism in a culture medium, optionally comprising an exogenous precursor such as, but not limited to lactose, lactoNbiose, N-acetyllactosamine and/or an aglycon, wherein said microorganism intracellularly dephosphorylates N-acetylglucosamine-6-phosphate to N-acetylglucosamine, converts N-acetylglucosamine to N-acetylmannosamine and convert the latter further to N-acetyl-neuraminate.

The present invention is in the technical field of synthetic biology and metabolic engineering. More particularly, the present invention is in the technical field of fermentation of metabolically engineered microorganisms. The present invention describes engineered microorganisms able to synthesize sialylated compounds via an intracellular biosynthesis route. These microorganisms can dephosphorylate N-acetylglucosamine-6-phosphate to N-acetylglucosamine and convert the N-acetylglucosamine to N-acetylmannosamine. These microorganisms also have the ability to convert N-acetylmannosamine to N-acetyl-neuraminate. Furthermore, the present invention provides a method for the large scale in vivo synthesis of sialylated compounds, by culturing a microorganism in a culture medium, optionally comprising an exogenous precursor such as, but not limited to lactose, lactoNbiose, N-acetyllactosamine and/or an aglycon, wherein said microorganism intracellularly dephosphorylates N-acetylglucosamine-6-phosphate to N-acetylglucosamine, converts N-acetylglucosamine to N-acetylmannosamine and convert the latter further to N-acetyl-neuraminate.

This disclosure is in the technical field of synthetic biology and metabolic engineering. The disclosure provides engineered viable bacteria having a reduced or abolished synthesis of poly-N-acetyl-glucosamine (PNAG), Enterobacterial Common Antigen (ECA), cellulose, colanic acid, core oligosaccharides, Osmoregulated Periplasmic Glucans and Glucosylglycerol (O), glycan, and trebalose. The disclosure further provides methods for the production of bioproduct by the viable bacteria and uses thereof. Furthermore, the disclosure is in the technical field of fermentation of metabolically engineered microorganisms producing bioproduct.

A method for preparing chondroitin sulfate oligosaccharides with a C5 protein targeting property, and an application thereof, relating to the technical field of biomedicine. The method uses squid chondroitin sulfate as a raw material to prepare chondroitin sulfate oligosaccharides using enzymatic hydrolysis, using the method to screen the activity of various types of oligosaccharides in order to obtain the fragment with the best activity; the method is highly scientific and feasible. The method further uses the screened chondroitin sulfate disaccharides; the mechanism of chondroitin sulfate disaccharides in the treatment of osteoarthritis by regulating the complement system is explored and revealed by in vitro and in vivo experiments to finally provide a new way of treating osteoarthritis, thus having good practical application value.

A method for preparing chondroitin sulfate oligosaccharides with a C5 protein targeting property, and an application thereof, relating to the technical field of biomedicine. The method uses squid chondroitin sulfate as a raw material to prepare chondroitin sulfate oligosaccharides using enzymatic hydrolysis, using the method to screen the activity of various types of oligosaccharides in order to obtain the fragment with the best activity; the method is highly scientific and feasible. The method further uses the screened chondroitin sulfate disaccharides; the mechanism of chondroitin sulfate disaccharides in the treatment of osteoarthritis by regulating the complement system is explored and revealed by in vitro and in vivo experiments to finally provide a new way of treating osteoarthritis, thus having good practical application value.

The present disclosure is in the technical field of synthetic biology and metabolic engineering. The disclosure provides engineered viable bacteria. In particular, the disclosure provides viable bacteria with reduced cell wall biosynthesis additionally modified for production of glycosylated product. The disclosure further provides methods of generating viable bacteria and uses thereof. Furthermore, the disclosure in the technical field of fermentation of metabolically engineered microorganisms producing glycosylated product.

The invention discloses a recombinant Corynebacterium glutamicum for efficient synthesis of highly pure hyaluronic acid and oligosaccharides thereof, belonging to the technical field of bioengineering. The recombinant Corynebacterium glutamicum constructed in the present invention can produce hyaluronic acid with a yield up to 40g/L, and a crude product purity of 95%. Addition of exogenous hyaluronic acid hydrolase and optimization of the fermentation conditions results in hyaluronic acid oligosaccharides with specific molecular weight, and can further improve the yield of hyaluronic acid to 72 g/L. The invention lays a solid foundation for the efficient synthesis of highly pure hyaluronic acid by microorganisms, and the constructed recombinant Corynebacterium glutamicum is suitable for industrial production and application.

The present disclosure relates to synthesis of heparin, which may be bioequivalent to porcine USP Heparin Sodium. The synthesis may involve three intermediates starting from heparosan.